This invention relates to a process for desulfurizing a gas stream having an H.sub.2 S content and a gas stream having an SO.sub.2 content. More specifically, the invention relates to a process for desulfurizing an industrial waste gas such as coke oven gas by contacting it with a citric acid or citrate-containing solution which has been contacted with an SO.sub.2 --containing gas such as sinter plant gas from an integrated steel mill. Sulfur is precipitated in the solution, and is removed therefrom. The gases from which a significant sulfur content has been removed can be re-used or passed to the atmosphere.
In the operation of an integrated steel mill, the sulfur content of coke oven exhaust and sinter plant gas pose a serious air pollution problem. Treatment procedures suggested in the past to significantly reduce the sulfur content of such gases have been either too inefficient or costly or both.